Problem: Solve for $n$, $ \dfrac{2n + 9}{n - 10} = \dfrac{1}{3} $
Answer: Multiply both sides of the equation by $n - 10$ $ 2n + 9 = \dfrac{n - 10}{3} $ Multiply both sides of the equation by $3$ $ 3(2n + 9) = n - 10 $ $6n + 27 = n - 10$ $5n + 27 = -10$ $5n = -37$ $n = -\dfrac{37}{5}$